Note that Suricata can automatically detect HTTP traffic regardless of
the port it uses. So the HTTP_PORTS variable is not nearly as
important as it is with Snort, if you use a Suricata enabled
ruleset.

In the suricata.yaml the default rule path is set followed by a list
of rule files. Suricata does not have a concept of shared object rules
or preprocessor rules. Instead of preprocessor rules, Suricata has
several rule files for events set by the decoders, stream engine, http
parser etc.